what you did not understand from the above code ?

Don't you know exists $is_prime{$_} part checks whether a key exists in a hash or not.

Don't you know $is_prime{$_} checks a value with the key in hash is true.(assuming your is_prime() function Boolean value(True or False))

All is well. I learn by answering your questions...

In reply to Re: Unable to Understand grep and hash use for prime no. by vinoth.ree
in thread Unable to Understand grep and hash use for prime no. by shankonit

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